Solar panels in Hauts-de-France
The calculator opens on Lille: change the commune, roof or usage. Below are the region’s five départements and what to know when sunshine is scarce.
Hauts-de-France is the region of mainland France where solar panels produce least: 1,113 kWh per kWp a year in the median commune, against 1,185 nationally, by our calculation on the European Commission’s PVGIS data. The best-placed département is Oise, at 1,125 kWh, the weakest Nord, at 1,086. That shortfall in sunshine shows far less in payback than in output. In Lille, a 3 kWp system for a household using 4,500 kWh a year pays back in 18.8 years, against 14.9 years in Marseille: the gap is real, but it is measured in years, not decades. The reason is the surplus feed-in tariff, now down to 1.1 c€/kWh: the gain comes mostly from electricity you no longer buy, and a household in the north uses as much during the day as one in the south.
Pays for itself in · 3 kWp in Lille
18.8 years
Net result over 20 years: +€377
| Output per year | 3,227 kWh |
| Used on site (48 %) | 1,540 kWh |
| Bill saving, year 1 | €308 |
| Surplus sold (1,687 kWh) | €19 |
| Standing-charge surcharge (export) | −€12 |
| Gain in year 1 | €315 |
| Share of your bill covered | 34 % |
| Price used (estimate) | €6,000 |
| Best-value size (estimated prices) | 2 kWc |
Month-by-month output in Lille (3 kWp)
December: 106 kWh; July: 383 kWh. PVGIS average 2005-2023.
Checked by Radif Partners · Editorial policy · Method and sources
The five départements
| Département | Median kWh/kWp | Communes: from… to… | 3 kWp pays back in |
|---|---|---|---|
| Oise (60) | 1,125 | 1,104 – 1,144 | 18.1 years |
| Aisne (02) | 1,122 | 1,057 – 1,158 | 18.6 years |
| Somme (80) | 1,116 | 1,093 – 1,139 | 18.6 years |
| Pas-de-Calais (62) | 1,105 | 1,085 – 1,138 | 18.7 years |
| Nord (59) | 1,086 | 1,043 – 1,126 | 18.8 years |
The range within the region is narrow, from 1,043 to 1,158 kWh per kWp: the northern plain has neither high ground nor a Mediterranean coast. What separates one project from another here is the house more than the commune: usage, roof facing, and shade from neighbouring buildings in the tightly packed brick streets of the Lille metropolitan area.
A very weak winter, a fair summer
In Lille, June output is about 3.6 times December’s. A household heated by electricity uses most of its power in winter; yet at 9,000 kWh a year its 3 kWp pays back in 12.9 years, because its base load (hot water, cooking, appliances) is enough to absorb summer output. Without electric heating and at 4,500 kWh, the reference household uses 48 % of what it produces.
How many years until your panels pay for themselves?
Pays for itself in
18.8 years
| Output per year | 3,233 kWh |
| Gain in year 1 | €315 |
| Installed price (estimate) | €6,000 |
| Net over 20 years | +€382 |
Département median, roof at 30° due south, surplus sold at 1.1 c€/kWh.
Before signing in the region
Sea air and wind on the coast matter for how modules are fixed: ask for the quote to specify the mounting system and its wind rating. Otherwise the rules are national: prior declaration, a single feed-in tariff and reduced VAT under conditions.